<template>
    <!-- 商品分类导航 -->
    <div class="type-nav">
        <div class="container">
            <div @mouseleave="leaveShow">
                <h2 class="all" @mouseenter="enterShow">全部商品分类</h2>
                <transition name="sort">
                    <div class="sort" v-show="show">
                        <div class="all-sort-list2">
                            <div class="item" v-for="(c1, index) in categoryList" :key="c1.categoryId"
                                @mouseenter="getIndex(index)" @click="goSearch">
                                <h3 :class="{show: currentIndex===index}">
                                    <a :data-categoryName='c1.categoryName'
                                        :data-category1Id='c1.categoryId'>{{c1.categoryName}}</a>
                                </h3>
                                <div class="item-list clearfix" :style="{display: currentIndex===index?'block':'none'}">
                                    <div class="subitem">
                                        <dl class="fore" v-for="(c2) in c1.categoryChild" :key="c2.categoryId">
                                            <dt>
                                                <a :data-categoryName='c2.categoryName'
                                                    :data-category2Id='c2.categoryId'>{{c2.categoryName}}</a>
                                            </dt>
                                            <dd>
                                                <em v-for="(c3) in c2.categoryChild" :key="c3.categoryId">
                                                    <a :data-categoryName='c3.categoryName'
                                                        :data-category3Id='c3.categoryId'>{{c3.categoryName}}</a>
                                                </em>
                                            </dd>
                                        </dl>
                                    </div>
                                </div>
                            </div>
                        </div>
                    </div>
                </transition>
            </div>
            <nav class="nav">
                <a href="###">服装城</a>
                <a href="###">美妆馆</a>
                <a href="###">尚品汇超市</a>
                <a href="###">全球购</a>
                <a href="###">闪购</a>
                <a href="###">团购</a>
                <a href="###">有趣</a>
                <a href="###">秒杀</a>
            </nav>

        </div>
    </div>
</template>

<script>
    import {
        mapGetters
    } from 'vuex';
    import throttle from 'lodash/throttle'

    export default {
        name: 'TypeNav',
        data() {
            return {
                //设置一个初始的index
                currentIndex: -1,
                show: true
            }
        },
        created() {
            // 判断路由的路径是否是home，不是的话就隐藏
            if (this.$route.path !== '/home') this.show = false;
        },
        computed: {
            ...mapGetters({
                //获取三级导航列表
                categoryList: 'getCategoryList'
            })
        },
        methods: {
            //鼠标移入时获取当前的索引，throttle用来进行节流
            getIndex: throttle(function (index) {
                this.currentIndex = index;
            }, 20),

            //点击导航栏进行跳转
            goSearch(e) {
                //获取到用于区分三级导航的自定义属性
                let {
                    categoryname,
                    category1id,
                    category2id,
                    category3id
                } = e.target.dataset;

                //判断所点击的标签是否时a标签
                if (categoryname) {
                    let location = {
                        name: 'search',
                        query: {
                            categoryName: categoryname
                        }
                    }
                    //判断所点击的内容时几级导航
                    if (category1id) {
                        location.query.category1Id = category1id;
                    } else if (category2id) {
                        location.query.category2Id = category2id;
                    } else if (category3id) {
                        location.query.category3Id = category3id;
                    }

                    //当前路由中有params就携带上
                    if (this.$route.params) {
                        location.params = this.$route.params;
                    }
                    //发送请求
                    if(this.$route.path !== '/home') {
                        this.$router.replace(location)
                    } else {
                        this.$router.push(location)
                    }
                }
            },

            //鼠标进入导航栏时
            enterShow() {
                //判断当前的路径是否是非home组件
                if (this.$route.path !== '/home') this.show = true;
            },

            //鼠标离开导航栏时
            leaveShow() {
                //currentIndex复位
                this.currentIndex = -1;
                //判断当前的路径是否是非home组件
                if (this.$route.path !== '/home') this.show = false;
            }
        }
    }
</script>

<style scoped lang='less'>
    .type-nav {
        border-bottom: 2px solid #e1251b;

        .container {
            width: 1200px;
            margin: 0 auto;
            display: flex;
            position: relative;

            .all {
                width: 210px;
                height: 45px;
                background-color: #e1251b;
                line-height: 45px;
                text-align: center;
                color: #fff;
                font-size: 14px;
                font-weight: bold;
            }

            .nav {
                a {
                    height: 45px;
                    margin: 0 22px;
                    line-height: 45px;
                    font-size: 16px;
                    color: #333;
                }
            }

            .sort {
                position: absolute;
                left: 0;
                top: 45px;
                width: 210px;
                position: absolute;
                background: #fafafa;
                z-index: 999;

                .all-sort-list2 {
                    .item {
                        h3 {
                            line-height: 30px;
                            font-size: 14px;
                            font-weight: 400;
                            overflow: hidden;
                            padding: 0 20px;
                            margin: 0;

                            a {
                                color: #333;
                            }

                            &.show {
                                background-color: #ddd;
                            }
                        }


                        .item-list {
                            display: none;
                            position: absolute;
                            width: 734px;
                            min-height: 460px;
                            background: #f7f7f7;
                            left: 210px;
                            border: 1px solid #ddd;
                            top: 0;
                            z-index: 9999 !important;

                            .subitem {
                                float: left;
                                width: 650px;
                                padding: 0 4px 0 8px;

                                dl {
                                    border-top: 1px solid #eee;
                                    padding: 6px 0;
                                    overflow: hidden;
                                    zoom: 1;

                                    &.fore {
                                        border-top: 0;
                                    }

                                    dt {
                                        float: left;
                                        width: 54px;
                                        line-height: 22px;
                                        text-align: right;
                                        padding: 3px 6px 0 0;
                                        font-weight: 700;
                                    }

                                    dd {
                                        float: left;
                                        width: 415px;
                                        padding: 3px 0 0;
                                        overflow: hidden;

                                        em {
                                            float: left;
                                            height: 14px;
                                            line-height: 14px;
                                            padding: 0 8px;
                                            margin-top: 5px;
                                            border-left: 1px solid #ccc;
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }

            .sort-enter {
                height: 0px;
            }

            .sort-enter-to {
                height: 461px;
            }

            .sort-enter-active {
                transition: all 0.3s linear;
            }
        }
    }
</style>